WIP: st-bin: Remove child as soon as it is destroyed
StBin seems to expect it already monitors child destruction:
st_bin_destroy (ClutterActor *actor)
{
StBinPrivate *priv = st_bin_get_instance_private (ST_BIN (actor));
if (priv->child)
clutter_actor_destroy (priv->child);
g_assert (priv->child == NULL);
but it didn't guarantee that and so the assertion would fail in some extensions. So now we monitor child destruction and remove it before the assertion is ever reached.
https://bugs.launchpad.net/bugs/1898005
https://bugs.launchpad.net/bugs/1898910
Edited by Daniel van Vugt